Apparatus, method, and program for validating user

ABSTRACT

User validation accuracy is improved without inconveniencing a user. When an authentication request packet is received from a terminal and the authentication is successful based on a user ID and a password, an HTTP header, user-agent information, and access source IP address are extracted from the packet, and user authentication is performed by verifying the IP address and the user-agent information against usage history information where at most two sets of the IP address and the user-agent information extracted from the authentication request packet which is received from the same user previously are registered. When the set of the IP address and the UA information corresponding to the new extracted IP address and the new extracted UA information is registered in the usage history information, the authentication is successful, and the usage history information is overwritten with the new IP address and the new UA information.

This is a Continuation of U.S. application Ser. No. 14/510,427 filedOct. 9, 2014, which is a Continuation of U.S. application Ser. No.13/679,401 filed Nov. 16, 2012 and issued as U.S. Pat. No. 9,021,555,which is a Continuation of U.S. application Ser. No. 11/886,902 filedSep. 21, 2007 and issued as U.S. Pat. No. 8,347,368, which is a NationalPhase of International Application No. PCT/JP2006/306501 filed Mar. 29,2006. The disclosure of the prior applications is hereby incorporated byreference herein in its entirety.

TECHNICAL FIELD

The present invention relates to an apparatus, a method, and a programfor validating a user, particularly to a user validation apparatus forvalidating whether or not a user operating a terminal device is a validuser, a user validation method which can be applied to the uservalidation apparatus, and a user validation program which causes acomputer to act as the user validation apparatus.

BACKGROUND ART

Generally a user validation method is adopted in a web site whichprovides predetermined online service to users who have registered inadvance, wherein, a user who accesses the web site through a terminaldevice is caused to input a user ID and a password, and a confirmationwhether or not the user who is accessing the web site is a valid user ismade based on whether or not a combination of the inputted user ID andpassword is registered. However, in the case that the user ID and thepassword are leaked to another person, the above user validation methodis disadvantageous because the person who knows the user ID and thepassword can illegally access the web site while disguising theiridentity as that of a valid user.

For example, Japanese Patent Application Laid-Open (JP-A) No.2000-209284 discloses a technique of performing user authentication bydetermining whether or not, in addition to the user ID and the password,a telephone number of a caller received from a telephone exchange isverified against a telephone number of a telephone line which is used bya registered user.

Japanese Patent Application Laid-Open (JP-A) No. 2001-325229 discloses atechnique, wherein an IP address (and link source URL) with which theusage of service is permitted is stored in a database along with ID andpassword and a determination whether or not the usage of service ispermitted is made, in addition to determination with the ID andpassword, by determining whether or not the access source IP address isregistered in the database (and when the link source URL exists in anaccess signal, by determining whether or not the link source URL isregistered in the database).

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention

In the techniques disclosed in Japanese Patent Application Laid-Open(JP-A) Nos. 2000-209284 and 2001-325229, the confirmation whether or notthe user who is operating the terminal device of the access source is avalid user (whether or not a third party disguises its identity as thatof a valid user) is made by determining whether or not the terminaldevice of the access source is a valid terminal device by using thetelephone number or the IP address. Although the technique disclosed inJapanese Patent Application Laid-Open (JP-A) No. 2000-209284 has anadvantage that the terminal device can uniquely be specified by usingthe telephone number, the technique has a problem in that the techniquecannot be applied to other devices except for the terminal deviceconnected to a network through the telephone exchange.

Although the IP address used in the technique disclosed in JapanesePatent Application Laid-Open (JP-A) No. 2001-325229 is always kept fixedin the terminal device to which a global IP address is fixedly imparted,few terminal devices have such fixedly imparted global IP address, andin most terminal devices, the IP address is different in each accessbecause a given IP address is automatically allocated from the manyglobal IP addresses possessed by an Internet service provider (theInternet provider, hereinafter simply referred to as “provider”) inaccessing the Internet and the like. Therefore, in the case where theuser validation or authentication is performed based on whether or notthe IP address is verified against the IP address registered in thedatabase like the technique disclosed in Japanese Patent ApplicationLaid-Open (JP-A) No. 2001-325229, there is a risk of mistaking theaccess of a valid user for the illegal access or mistaking the illegaluser for a valid user.

As a technique of to prevent spoofing and improve a degree of security,a technique of performing an authentication of a terminal device byusing an electronic certificate prior to the user authentication basedon the user ID and the password. By applying the technique, even if theuser ID and the password are leaked to another person, a fraud can beprevented unless a person who knows the user ID and the passwordoperates the terminal device in which the legitimate electroniccertificate is installed. However, in order to apply the technique, itis necessary to perform a troublesome task of installation of theelectronic certificate in the terminal device, which results in aproblem of a large burden to a user.

In view of the foregoing, an object of the invention is to obtain a uservalidation apparatus, a user validation method, and a user validationprogram which can improve accuracy of user validation without reducinguser's convenience.

Means for Solving the Problem

In the case where HTTP (Hyper Text Transfer Protocol) is applied as aprotocol of an application layer in communication with the terminaldevice, an HTTP header is added to a packet received from the terminaldevice, and the user-agent information is included in the HTTP header.In the user-agent information, a format and the like are not defined onthe HTTP protocol, and any character string can be set. For example, inthe case where the terminal device is a computer such as a PC (PersonalComputer) while an application for transmitting the packet from thecomputer is a browser (browsing software), information indicating aversion and the like of an OS (Operating System) running on the computerand information indicating a version and the like of the browser are setas the user-agent information in a default setting of the browser.Depending on a user operating the computer, sometimes the settings ofthe browser and the like are updated in advance such that the desiredcharacter string is transmitted as the user-agent information.

The user-agent information set by the default setting of the browserincludes information indicating how many patches are applied to the OSor the browser in addition to the information of the versions of the OSand the browser. Therefore, in the case where the user-agent informationis set by the default-setting browser, although the terminal deviceswhich transmit the same user-agent information exist, a degree ofdifference among the pieces of the user-agent information transmittedfrom the terminal devices is high. Contents of the user-agentinformation are updated when a new patch is made in the OS or thebrowser or when the version upgrade or conversion is performed, however,because the new patch for OS or the browser or the version upgrade orconversion occurs extremely less frequently, it can be deemed that theuser-agent information transmitted from the individual terminal deviceis substantially kept fixed. In the case where the user sets theuser-agent information in advance so as to transmit the desiredcharacter string, the degree of difference among the pieces of theuser-agent information transmitted from the terminal devices becomeshigher.

The inventor focuses attention on the above fact to reach the inventionby achieving that the user-agent information which is set in the HTTPheader of the packet received previously from the terminal deviceoperated by a certain user is stored, and the user-agent information setin the HTTP header of the packet received from the terminal deviceoperated by the user who is estimated to be the same person is verifiedagainst the stored user-agent information, and accordingly, adetermination whether or not the terminal device which transmits thecurrently received packet is identical to the terminal device whichtransmits the packet received previously can be made, and the accuracyof user validation can be improved.

A user validation apparatus of claim 1 of the invention is configured toinclude an extraction unit which extracts user-agent information set inan HTTP header of a packet received from a terminal device by applyingHTTP as a protocol of an application layer; an information managementunit which stores the user-agent information extracted by the extractionunit from the packet received from the terminal device, which isoperated by an individual user, in a storage unit so as to correspond touser identification information of the individual user; and adetermination unit which determines whether or not a user operating agiven terminal device is a valid user by verifying user-agentinformation extracted by the extraction unit from a packet received fromthe given terminal device, against user-agent information stored in thestorage unit so as to correspond to user identification information ofthe user operating the given terminal device.

The invention of claim 1 includes the extraction unit which extracts theuser-agent information set in the HTTP header of the packet receivedfrom the terminal device by applying HTTP as a protocol of anapplication layer, and the information management unit stores theuser-agent information extracted from the packet received from theterminal device, which is operated by the individual user, in thestorage unit so as to correspond to the user identification informationof the individual user. A user ID inputted by the individual useroperating the terminal device and another identification informationuniquely defined from the user ID may be applied to the useridentification information. The user-agent information may directly bestored in the storage unit, preferably from the viewpoint of security,the user-agent information may be stored in the storage unit afterencrypted by using a known encryption method such as a method with ahash function and the like.

The determination unit of claim 1 of the invention determines whether ornot the user operating the given terminal device is a valid user byverifying the user-agent information extracted by the extraction unitfrom the packet received from the given terminal device, against theuser-agent information which is stored in the storage unit so as tocorrespond to the user identification information of the user operatingthe given terminal device. As described above, because it can be deemedthat the user-agent information transmitted from each terminal device issubstantially kept fixed, by verifying the user-agent informationextracted from the received packet against the user-agent informationstored in the storage unit so as to correspond to the useridentification information of the user operating the given terminaldevice, it can be determined whether or not the terminal device fromwhich the packet is currently received is the terminal device which ispreviously used by the same user, and, based on the determination, itcan be determined whether or not the user operating the terminal devicefrom which the packet is currently received is a valid user.

In the case where HTTP is applied as the protocol of the applicationlayer, because the user-agent information is always set in the HTTPheader of the packet received from the terminal device, the user(terminal device) confirmation with the user-agent information hasgreater versatility than that of the technique disclosed in JapanesePatent Application Laid-Open (JP-A) No. 2000-209284 which cannot beapplied to the terminal devices except for the terminal device connectedto the network through the telephone exchange, and the user confirmationwith the user-agent information has the accuracy of confirmation higherthan that of the technique of using the IP address which is probablychanged in each access. Additionally, the troublesome task such as theinstallation of the electronic certificate in the terminal device is notrequired in the user confirmation with the user-agent information.Accordingly, the invention of claim 1 can improve the accuracy of uservalidation without reducing the user's convenience.

In the invention of claim 1, when IP (Internet Protocol) is applied as aprotocol of an Internet layer in communication with the terminal device,for example as described in claim 2, it is preferably configured suchthat the extraction unit further extracts an access source IP addressfrom the packet, the information management unit stores the accesssource IP address and the user-agent information extracted by theextraction unit from a packet received from a terminal device operatedby an individual user, in the storage unit so as to correspond to useridentification information of the individual user, and the determinationunit determines whether or not a user operating a given terminal deviceis a valid user by determining whether or not an access source IPaddress and user-agent information extracted from a packet received fromthe given terminal device correspond to an access source IP address anduser-agent information stored in the storage unit so as to correspond touser identification information of the user operating the given terminaldevice.

As described above, although it can be deemed that the user-agentinformation transmitted from each terminal device is substantially keptfixed, in a default setting of the application such as a browser,contents of the user-agent information are changed when a new patch isapplied to an OS or the browser or when a version upgrade or exchange ofthe OS or the browser is performed. In the case where the user performsa setting such that a desired character string is transmitted as theuser-agent information, the character string transmitted as theuser-agent information may be changed by the user. On the other hand,although the IP address allocated to the individual terminal device maybe possibly different in each access, the IP addresses (global IPaddresses) for allocating the terminals which are possessed by theindividual provider are different from one another within a fixed range,and each terminal accesses the web site through the fixed provider, andtherefore, although the IP address allocated to the individual terminalin each access is not always kept fixed, the degree of coincidence ishigh in the case, for example, the upper several bits are always keptfixed.

On the basis of the above, in the invention of claim 2, an access sourceIP address in addition to the user agent information is extracted fromthe packet, the access source IP address and the user-agent informationextracted by the extraction unit from the packet received from theterminal device operated by an individual user, is stored in the storageunit so as to correspond to the user identification information of theindividual user, and it is determined whether or not the user operatinga given terminal device is a valid user by determining whether or notthe access source IP address and the user-agent information extractedfrom the packet received from the given terminal device correspond tothe access source IP address and the user-agent information which arestored in the storage unit so as to correspond to the useridentification information of the user operating the given terminaldevice, and accordingly, the accuracy of user validation can further beimproved.

In providing service (referred to as information-transmitting service)in which certain information is distributed to the individual user whichhas been registered in advance according to a request of the individualuser, in the case where the user validation apparatus according to theinvention is used when confirming whether or not the user who requeststhe distribution of the information is a valid user (who has beenregistered in advance), a demand level of the accuracy of uservalidation for the user validation apparatus is relatively low, on thecontrary, in the case where different kinds of service are provided tothe individual users such that financial transactions such as balanceinquiry, deposits and withdrawals inquiry, direct deposit, and moneytransfer are performed according to an instruction from the individualuser, the extremely high accuracy of user validation may be required forthe user validation apparatus according to the invention.

Therefore, in the invention of claim 1 or 2, for example as described inclaim 3, it may be configured such that the storage unit stores apassword set in advance for each individual user so as to correspond tothe user identification information of the individual user, and thedetermination unit makes the determination (whether the user operatingthe given terminal device is a valid user) based on informationextracted by the extraction unit, when a combination of the useridentification information and the password inputted by the useroperating the given terminal device is stored in the storage unit. Inthe invention of claim 3, in addition to the conventional uservalidation (authentication) based on the combination of the useridentification information and the password, the user validation isperformed based on the user-agent information (and the access source IPaddress), and therefore, the accuracy of user validation can further beimproved, and additionally, even if a third party which illegallyobtains the user identification information and the password of a validuser illegally accesses the web site while disguising their identity asthat of a valid user, the illegal access can be detected and prevented.

Although the IP address allocated to the terminal device is different ineach access, the degree of coincidence is high in the IP address in eachaccess. From this standpoint, in the invention of claim 2, for exampleas described in claim 4, the determination unit is preferably configuredsuch that, for the access source IP address extracted from the receivedpacket, the determination unit determines whether or not the accesssource IP address extracted from the received packet corresponds to theaccess source IP address stored in the storage unit by determiningwhether or not a coincidence ratio in a predetermined bit unit to theaccess source IP address stored in the storage unit is equal to orhigher than a threshold, and, for the user-agent information extractedfrom the received packet, the determination unit determines whether ornot the user-agent information extracted from the received packetcorresponds to the user-agent information stored in the storage unit bydetermining whether or not the user-agent information extracted from thereceived packet is identical to the user-agent information stored in thestorage unit. Therefore, it can accurately be determined whether or notthe access source IP address and the user-agent information extractedfrom the received packet correspond to the access source IP address andthe user-agent information stored in the storage unit.

In the invention of claim 1 or 2, in the case where the access from theindividual user is restricted only to an access from each fixed terminaldevice, each one piece of the user-agent information (and the accesssource IP address) may be stored in the storage unit for the individualuser, and therefore, in the invention of claim 2, when the individualuser can be permitted to access from each indefinite terminal device,for example as described in claim 5, the information management unit ispreferably configured such that, as a result of verifying the accesssource IP address and the user-agent information extracted from thereceived packet against the access source IP address and the user-agentinformation stored in the storage unit, when the determination unitdetermines that the access source IP address and the user-agentinformation extracted from the received packet do not correspond to theaccess source IP address and the user-agent information stored in thestorage unit, the information management unit additionally stores theaccess source IP address and the user-agent information extracted fromthe received packet in the storage unit so as to correspond to the useridentification information, and, when the plurality of sets of theaccess source IP address and the user-agent information are stored inthe storage unit so as to correspond to the user identificationinformation of the user operating the given terminal device, thedetermination unit determines whether or not the user operating thegiven terminal device is a valid user by respectively verifying theaccess source IP address and the user-agent information extracted fromthe packet received from the given terminal against a plurality of setsof the access source IP address and the user-agent information.

In the invention of claim 5, in the case where the individual useraccesses the web site through the new terminal device which is not usedpreviously, the determination unit determines that the access source IPaddress and the user-agent information extracted from the receivedpacket are the access source IP address and the user-agent informationstored in the storage unit, and thereby it is determined that the useris not a valid user, in this case, the information management unitadditionally stores the access source IP address and the user-agentinformation extracted from the received packet in the storage unit so asto correspond to the user identification information. When the pluralsets of the access source IP address and the user-agent informationcorresponding to the user identification information of the useroperating the given terminal device are stored in the storage unit, thedetermination unit respectively verifies the access source IP addressand the user-agent information extracted from the packet received fromthe given terminal device against the plural registered sets of theaccess source IP address and the user-agent information, and thereby itis determined whether or not the user operating the given terminaldevice is a valid user, and accordingly, in the subsequent accessesthrough the new terminal device, it is determined that user operatingthe given terminal device is a valid user.

Thus, according to the invention of claim 5, the individual user canaccess by using a desired terminal device in plural terminal devicessuch as terminal devices placed in home or in the office. Even if theindividual user are permitted to access the web site from eachindefinite terminal device, the number of terminal devices used by theindividual user is frequently limited, and therefore it is hardlydetermined in each time that the user is not a valid user since the userhardly accesses the web site through the new terminal device in eachtime.

In the invention of claim 5, in the case where it is determined that theaccess source IP address and the user-agent information extracted fromthe received packet do not correspond to the access source IP addressand the user-agent information stored in the storage unit, theinformation management unit may additionally stores the access source IPaddress and the user-agent information in the storage unit only when theuser operating the terminal device of the packet source is validated tobe a valid user by a method different from the determination unit.

In the invention of claim 5, for example as described in claim 6, thedetermination unit may be configured such that, when the plurality ofsets of the access source IP address and the user-agent information arestored in the storage unit so as to correspond to the useridentification information of the user operating the given terminaldevice, the determination unit determines that the user operating thegiven terminal device is a valid user when the access source IP addressand the user-agent information extracted from the received packetcorrespond to at least one set of the access source IP address and theuser-agent information among the plurality of sets of the access sourceIP address and the user-agent information stored in the storage unit.Therefore, even if a valid user accesses the web site by selectivelyusing the plural terminal devices, the determination of a valid user canbe made with high accuracy.

In the invention of claim 5, for example as described in claim 7, thedetermination unit may be configured such that, when the plurality ofsets of the access source IP address and the user-agent information arestored in the storage unit so as to correspond to the useridentification information of the user operating the given terminaldevice, the determination unit determines that the user operating thegiven terminal device is not a valid user when no set of the accesssource IP address and the user-agent information, that is determined torespectively correspond to the access source IP address and theuser-agent information extracted from the received packet, exists amongthe plurality of sets of the access source IP address and the user-agentinformation stored in the storage unit. Accordingly, even if a thirdparty which is not a valid user accesses the web site, by comparing withthe past access, it can be determined that it is not a valid user basedon the fact that at least one of the access source IP address or theuser-agent information differs from the access source IP address and theuser-agent information stored in the storage unit. Therefore, the thirdparty which is not a valid user can accurately be distinguished from avalid user.

In the invention of claim 7, even if the user operating the terminaldevice of the packet source is a valid user, in the case of theparticular usage environment such as the case in which the user accessesthe web site in each time by using a different terminal device in theplural terminal devices, and the case in which, although the useraccesses the web site by using the fixed terminal device, the terminaldevice used for the access is a portable terminal device such as anotebook PC, or the user accesses the web site in each time by using adifferent hot spot (a site where public wireless LAN can be used), andisadvantage in that it is determined that the user operating theterminal device of the packet source is not a valid user, because no setof the access source IP address and the user-agent information which isdetermined to respectively correspond to the access source IP addressand the user-agent information extracted from the received packet existsamong the plural sets of the access source IP address and the user-agentinformation stored in the storage unit.

In consideration of the above, in the invention of claim 7, for exampleas described in claim 8, the information management unit is preferablyconfigured such that, when notified that the user who has beendetermined by the determination unit not to be a valid user, has beendetermined to be a valid user by a confirmation method different fromthe user validation of the determination unit, the informationmanagement unit stores predetermined identification information in thestorage unit so as to correspond to the user identification informationof the user, and the determination unit determines that the useroperating the given terminal device is a valid user when thepredetermined identification information is stored in the storage unitso as to correspond to the user identification information of the useroperating the given terminal device and when, among the plurality ofsets of the access source IP address and the user-agent information,more than one set of the access source IP address and the user-agentinformation exists which is determined to correspond to the accesssource IP address extracted from the received packet, or when more thanone set of the access source IP address and the user-agent informationexists which is determined to correspond to the user-agent informationextracted from the received packet.

In the invention of claim 8, when notified that the user who has beendetermined by the determination unit not to be a valid user, has beendetermined to be a valid user by the confirmation method different fromthe user validation of the determination unit, it is deemed that theuser has the special usage environment, and the predeterminedidentification information is stored in the storage unit so as tocorrespond to the user identification information. For the user of whichthe predetermined indication information is stored in the storage unit,it is determined that the user operating the given terminal is a validuser when, among the plurality of sets of the access source IP addressand the user-agent information, more than one sets of the access sourceIP address and the user-agent information exists, which is determined tocorrespond to the access source IP address extracted from the receivedpacket, or when more than one sets of the access source IP address andthe user-agent information exists, which is determined to correspond tothe user-agent information extracted from the received packet.

Therefore, for example, in the case where a valid user accesses the website in each time by using the different terminal device in the pluralterminal devices, it can be determined that the user is a valid userbased on the fact that more than one sets of the access source IPaddress and the user-agent information exists which is determined tocorrespond to the access source IP address extracted from the receivedpacket among the plural stored sets of the access source IP address andthe user-agent information. In the case where a valid user accesses theweb site by using the different hot spot with the portable terminaldevice each time, it can be determined that the user is a valid userbased on the fact that more than one sets of the access source IPaddress and the user-agent information exists which is determined tocorrespond to the user-agent information extracted from the receivedpacket among the plural stored sets of the access source IP address andthe user-agent information. Accordingly, according to the invention ofclaim 8, the user validation can be performed with high accuracy even ifthe user has the special usage environment.

In the invention of claim 1 or 2, for example as described in claim 9,the user validation apparatus preferably further includes an electronicmail address storage unit which stores an electronic mail address usedby the individual user so as to correspond to the user identificationinformation of the individual user; and a transmission unit whichtransmits the electronic mail, at which a link to a predetermined webpage is added in order to confirm whether or not the user is a validuser by a method different from the determination unit, to theelectronic mail address stored in the electronic mail address storageunit so as to correspond to the user identification information of theuser, when the determination unit determines that the user operating thegiven terminal device is not a valid user. Accordingly, an operation bywhich the user, who has been determined not to be a valid user, receivesthe validation whether or not the user is a valid user by a methoddifferent from the determination unit becomes simple, and the burden tothe user who has been determined not to be a valid user can be reduced.

In the invention of claim 5, for example as described in claim 10, theinformation management unit may be configured such that, as a result ofverifying the access source IP address and the user-agent informationextracted from the received packet against each of the plurality of setsof the access source IP address and the user-agent information stored inthe storage unit, when the determination unit determines that the accesssource IP address and the user-agent information extracted from thereceived packet do not correspond to any one of plurality of sets of theaccess source IP address and the user-agent information stored in thestorage unit, and when the number of sets of the access source IPaddress and the user-agent information stored in the storage unit so asto correspond to the user identification information of the useroperating the given terminal device reaches a predetermined upper limitvalue, the information management unit updates the set of the accesssource IP address and the user-agent information, of which time whichhas been stored in the storage unit is the earliest in the plurality ofsets of the access source IP address and the user-agent informationstored in the storage unit, with the access source IP address and theuser-agent information extracted from the received packet, and storesthe access source IP address and the user-agent information extractedfrom the received packet in the storage unit.

Accordingly, the number of sets of the access source IP address and theuser-agent information stored in the storage unit for the individualuser can be prevented from exceeding the upper limit value, the storagecapacity of the storage unit can be saved, and additionally, the numberof sets of the access source IP address and the user-agent informationwhich the determination unit verifies against the access source IPaddress and the user-agent information extracted from the receivedpacket also becomes equal to the upper limit value or less, and therebythe large burden applied to the determination unit can be prevented.

In the invention of claim 10, when the determination unit determinesthat the access source IP address and the user-agent informationextracted from the received packet do not correspond to any one of theplurality of sets of the access source IP address and the user-agentinformation stored in the storage unit, and when the number of sets ofthe access source IP address and the user-agent information stored inthe storage unit so as to correspond to the user identificationinformation of the user operating the given terminal device reaches apredetermined upper limit value, the information management unitoverwrites and stores the new access source IP address and the newuser-agent information extracted from the received packet in the storageunit, only when it is confirmed that the user operating the terminaldevice of a packet source is a valid user by a method different from thedetermination unit.

On the other hand, in the invention of claim 10, when the determinationunit determines that the access source IP address and the user-agentinformation extracted from the received packet do not correspond to anyone of the plural sets of the access source IP address and theuser-agent information stored in the storage unit and, when the numberof sets of the access source IP address and the user-agent informationstored in the storage unit so as to correspond to user identificationinformation of the user operating the given terminal device reaches thepredetermined upper limit value, in the case where the informationmanagement unit overwrites and stores the new access source IP addressand the new user-agent information with no condition (as describedabove, not depending on whether or not it is confirmed that the user isa valid user by the method different from the determination unit), theinformation corresponding to a valid user may be possibly overwrittenand deleted when the new access source IP address and the new user-agentinformation are information corresponding to the illegal access, and inthis case, by determining that the access from a valid access is “not avalid user”, and thereby effects that the existence of the illegalaccess can be detected can be obtained.

In the invention of claim 5, for example as described in claim 11, theinformation management unit is preferably configured such that, as aresult of respectively verifying the access source IP address and theuser-agent information extracted from the received packet against theplurality of sets of the access source IP address and the user-agentinformation stored in the storage unit, when the determination unitdetermines that the access source IP address and the user-agentinformation extracted from the received packet correspond to a specificset of the access source IP address and the user-agent information amongthe plurality of sets of the access source IP address and the user-agentinformation stored in the storage unit, the information management unitoverwrites the specific set of the access source IP address and theuser-agent information with at least the user-agent information of theset of the access source IP address and the user-agent informationextracted from the received packet, and stores the user-agentinformation in the storage unit.

As described above, in the case where the default setting of theapplication such as the browser is used, contents of the user-agentinformation are changed when the new patch is applied to the OS or thebrowser, or when the version upgrade or exchange of the OS or thebrowser is performed. In the case where the user performs the settingsuch that the desired character string is transmitted as the user-agentinformation, contents of the user-agent information are changed when theuser changes the character string transmitted as the user-agentinformation. However, once the contents of user-agent information arechanged, the contents are not changed for a while. Therefore, asdescribed above, the specific set of the access source IP address andthe user-agent information which is determined to correspond to theaccess source IP address and the user-agent information stored in thestorage unit is overwritten without at least the user-agent informationof the access source IP address and the user-agent information extractedfrom the received packet, and the user-agent information is stored inthe storage unit, and thereby, for at least the user-agent information,the latest information is stored in the storage unit, and the accuracyof subsequent user validation can be improved. In the invention of claim11, obviously the access source IP address extracted from the receivedpacket may be overwritten and stored along with the user-agentinformation.

A user validation method of claim 12 of the invention includesextracting user-agent information set in an HTTP header of a packetreceived from a terminal device operated by an individual user byapplying HTTP as a protocol of an application layer, and storing theextracted user-agent information in a storage unit so as to correspondto user identification information of the individual user; andextracting user-agent information set in an HTTP header of a packetreceived from a given terminal device by applying HTTP as the protocolof the application layer, and determining whether or not a useroperating the given terminal device is a valid user by verifying theextracted user-agent information against user-agent information storedin the storage unit so as to correspond to user identificationinformation of the user operating the given terminal device.Accordingly, similarly to the invention of claim 1, the accuracy of uservalidation can be improved without reducing the user's convenience.

A user validation program of claim 13 of the invention causes a computercomprising a storage unit to act as: an extraction unit which extractsuser-agent information set in an HTTP header of a packet received from aterminal device by applying HTTP as a protocol of an application layer;an information management unit which stores the user-agent informationextracted by the extraction unit from the packet received from theterminal device, which is operated by an individual user, in a storageunit so as to correspond to user identification information of theindividual user; and a determination unit which determines whether ornot a user operating a given terminal device is a valid user byverifying user-agent information extracted by the extraction unit from apacket received from the given terminal device against user-agentinformation which is stored in the storage unit so as to correspond touser identification information of the user operating the given terminaldevice.

A user validation program of claim 13 of the invention causes a computercomprising the storage unit to act as the extraction unit, theinformation management unit, and the determination unit, andaccordingly, the computer executes the user validation program of claim13, and thereby the computer acts as the user validation apparatus ofclaim 1, and therefore, similarly to the invention of claim 1, theaccuracy of user validation can be improved without reducing the user'sconvenience.

Effect of the Invention

As described above, in the invention, the user-agent informationextracted from the HTTP header of the packet, which is received from theterminal device operated by the individual user by applying HTTP as theprotocol of the application layer to the terminal device, is stored inthe storage unit so as to correspond to the user identificationinformation of the individual user, and, the user-agent informationextracted from the HTTP header of the packet received from the giventerminal device is verified against the user-agent information which isstored so as to correspond to the user identification information of theuser operating the given terminal device, and thereby it is determinedwhether or not the user operating the given terminal device is a validuser. Therefore, the invention has the excellent effect of being able toimprove the accuracy of user validation without reducing the user'sconvenience.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a schematic configuration of acomputer system according to an embodiment;

FIG. 2 is a conceptual view explaining addition and removal of a headerin each layer when HTTP data is transmitted from a client terminal to aserver;

FIG. 3 is a flowchart showing contents of a user authentication processperformed by an application server;

FIG. 4 is a schematic view showing contents of usage historyinformation;

FIG. 5 is a view showing a criterion for authentication success/failurebased on the usage history information;

FIG. 6 is a screen image showing an example of a re-authenticationrequest e-mail;

FIG. 7 is a flowchart showing contents of a usage history table updateprocess; and

FIG. 8 is a screen image showing an example of a confirmation e-mail.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the invention will be described in detail withreference to the drawings. FIG. 1 shows a computer system 10 accordingto the embodiment. The computer system 10 of the embodiment includes aweb server 12 placed in a financial institution. The web server 12includes CPU 12A, a memory 12B formed by RAM and the like, a hard diskdrive (HDD) 12C, and a network interface (I/F) unit 12D. Anauthentication information database (DB) and a usage history table(described in detail later) are stored in HDD 12C, and HDD 12Ccorresponds to the storage unit according to the invention. A userauthentication program is installed in HDD 12C, and CPU 12A performs alater-mentioned user authentication process using the userauthentication program. The user authentication program corresponds tothe user validation program of claim 13, CPU 12A executes the userauthentication program, and thereby the web server 12 acts as the uservalidation apparatus according to the invention.

The network I/F unit 12D of the web server 12 is directly connected to acomputer network (the Internet) 16 in which many web servers areconnected to one another through a communication line, and the networkI/F unit 12D is also connected to an intranet (LAN) 26 which is placedin a financial institution. An account system 28 is connected to theintranet 26. Many client terminals 18 formed by PCs and the like areconnected to the Internet 16. The browser is installed in each clientterminal 18, and the client terminal 18 corresponds to the terminaldevice according to the invention. In the mode in which the clientterminal 18 is connected to the Internet 16, there is a case in that theclient terminal 18 may be directly connected to the Internet 16 like theclient terminal designated by the numeral 18A of FIG. 1 (particularlythe client terminal 18 is connected to the Internet 16 through aprovider (not shown)), and there is another case in that the clientterminal 18 may be connected to the Internet 16 through a proxy server22 placed in a firm like the client terminal designated by the numeral18B.

Next, operation of the embodiment will be described. The financialinstitution according to the embodiment provides online financialtransaction acceptance service as service with which the user having abank account of the financial institution can perform an onlinefinancial transaction, wherein an instruction for executing the onlinefinancial transaction is accepted from the user who uses an onlinefinancial transaction web site operated by the web server 12. In thefinancial transaction utilizing the online financial transactionacceptance service, the user browses a web page of the online financialtransaction web site through the client terminal 18, and the user inputsnecessary information of the web page to transmit information (financialtransaction instruction information) for providing an instruction forexecuting the financial transaction desired by the user to the webserver 12 through the client terminal 18. The financial transactioninstruction information is transferred from the web server 12 to theaccount system 28 connected to the intranet 26, and thereby thefinancial transaction instructed by the user is performed by the accountsystem 28 based on the financial transaction instruction information.

The user who uses the online financial transaction acceptance serviceapplies for the usage of the service to the financial institution inadvance. The financial institution imparts a user ID (corresponds to theuser identification information according to the invention) to the usereach time the user applies for the usage of the service, and thefinancial institution registers the imparted user ID along with apassword (corresponds to the authentication information according to theinvention) and an electronic mail address noticed from the user(electronic mail address used by the user) in the authenticationinformation DB stored in HDD 12C of the web server 12. Thus, HDD 12Ccorresponds to the storage unit of claim 3 and the electronic mailaddress storage unit of claim 9.

Then, the packet which is transmitted from the client terminal 18 to theweb server 12 when the user provides the instruction for accessing theonline financial transaction web site through the client terminal 18will be described. In the communication between the client terminal 18and the web server 12 through the Internet 16, IP is applied as theprotocol of an Internet layer, TCP (Transmission Control Protocol) isapplied as the protocol of a transport layer, and HTTP is applied as theprotocol of an application layer. The instruction for accessing theonline financial transaction web site is provided in such a manner thatthe user operates an input device of the client terminal 18 to specifyURL (Uniform Resource Locator) of the online financial transaction website in the condition that the browser has been launched on the clientterminal 18.

When the instruction for accessing the online financial transaction website is provided, the browser which is an application program forperforming a process corresponding to the application layer generatesHTTP data, at which information necessary to make a request fordistributing the web page corresponding to the specified URL is set, andadds the HTTP header, at which Information corresponding to theapplication layer is set, to a leading end of the HTTP data (see FIG.2). In the case where a later-mentioned authentication request packet istransmitted from the client terminal 18 to the web server 12,information including the user ID and the password which the userinputted through the client terminal 18 are set in the HTTP data. Theuser-agent information is included in the information set in the HTTPheader, and the information indicating the version of the OS or thebrowser running on the client terminal 18 and the information indicatinghow many patches are applied are set as the user-agent information inthe default-setting browser. The browser setting can be changed suchthat a given character string is fixedly set as the user-agentinformation, and the character strings which has been specified inadvance is set as the user-agent information when the setting ischanged.

Processing modules which perform processes corresponding to thetransport layer, the Internet layer, and the network interface layerrespectively are operating on the client terminal 18. As shown in FIG.2, the information generated by the browser (HTTP data to which the HTTPheader is added) is sequentially transferred from an upper-layerprocessing module to a lower-layer processing module, and the processingmodule of each layer performs a process corresponding to each layer anda process of adding a header, in which information corresponding to eachlayer is set, to the leading end of the transferred information.Therefore, the client terminal 18 transmits the HTTP data in the form ofthe packet to web server 12 to which a network header corresponding tothe network interface layer, an IP header corresponding to the Internetlayer, a TCP header corresponding to the transport layer, and the HTTPheader corresponding to the application layer are added respectively.

Information such as a destination IP address indicating a destination ofthe packet and a source IP address (IP address imparted to the clientterminal 18) are set as information corresponding to the Internet layerin the IP header by the processing module corresponding to the Internetlayer. Information such as a TCP port number is set as informationcorresponding to the transport layer in the TCP header by the processingmodule corresponding to the transport layer.

The processing modules of the layers are operating on the web server 12,and the packet from the client terminal 18 is sequentially transferredfrom the lower-layer processing module to the upper-layer processingmodule. The processing module of each layer refers to the headercorresponding to each layer which is added to the leading end of thetransferred packet, and performs the process corresponding to each layerbased on the information set in the header, and then the processingmodule performs a process of removing the header. Therefore, the HTTPdata in which only the HTTP header is added to the leading end thereofis transferred to the processing module (also including a processingmodule performing a later-mentioned user authentication process) of theapplication layer operating on the web server 12.

In the later-mentioned user authentication process, the web server 12performs a process using the source IP address (access source IPaddress) set in the IP header of the packet received from the clientterminal 18. However, the source IP address cannot be detected becausethe IP header has been already removed at the time the processing moduleperforming the user authentication process receives the packet.Therefore, the processing module of the Internet layer operating on theweb server 12 performs a process of adding the source IP address, set inthe IP header of the packet received from the client terminal 18, to theHTTP data, and thereby the source IP address is transmitted to theprocessing module (which performs the user authentication process) ofthe application layer.

In the web server 12, when a certain packet is received from the clientterminal 18 through the Internet 16, a predetermined processing module(which is also the processing module corresponding to the applicationlayer) running on the web server 12 determines whether or not the packetreceived from the client terminal 18 is an authentication request packetbased on whether or not predetermined information is set in the HTTPdata.

The online financial transaction web site is an aggregate of the manyweb pages correlated with one another by a link, and a financialtransaction execution instruction page is displayed by tracking back thelink from the home page of the web site, in which the user can specify acondition of the financial transaction which the user desires andprovide an instruction to perform the financial transaction. Inputfields for inputting the user ID and the password are provided, and amessage for encouraging the user to perform a login operation (input ofthe user ID and the password) is also displayed in the home page of theonline financial transaction web site. When the user inputs the user IDand the password in the corresponding input fields of the home page andtransmits the user ID and the password, the authentication requestpacket in which predetermined information is set in the HTTP data istransmitted from the client terminal 18 which the user operates.

When a predetermined processing module determines that the packetreceived from the client terminal 18 is not the authentication requestpacket, the predetermined processing module performs a processcorresponding to the received packet, e.g., a process in which the HTTPdata for distributing the home page data of the online financialtransaction web site to the source client terminal 18 is generated toadd the HTTP header to the generated HTTP data. The HTTP data and HTTPheader are transmitted as the packet to the client terminal 18 through aprocess opposite the process shown in FIG. 2. Therefore, the web pagewhich the user has requested through the client terminal 18 is displayedon a display of the client terminal 18.

On the other hand, when the predetermined processing module determinesthat the packet received from the client terminal 18 is theauthentication request packet, the predetermined processing modulestarts a processing module which performs the user authenticationprocess. Therefore, the user authentication program is executed by CPU12A, and the user authentication process shown in FIG. 3 is performed.

In the user authentication process, the user ID and the password areextracted from the HTTP data of the received authentication requestpacket in Step 30, and an authentication process of searching whether ornot the combination of the user ID and the password extracted in Step 30is registered in the authentication information DB is performed in Step32. In Step 34, it is determined whether or not the authentication issuccessful in the authentication process of Step 32 based on whether ornot the combination of the user ID and the password is extracted fromthe authentication information DB by the search of Step 32. When thedetermination is negative, the flow goes to Step 74, the predeterminedprocessing module of the start-up source is notified of theauthentication failure, and the user authentication process is ended. Inthis case, the predetermined processing module performs an error processof displaying a message for notifying that the inputted user ID orpassword is wrong on the display of the client terminal 18 of theauthentication request packet source.

On the other hand, when the authentication is successful in theauthentication process of Step 32 (which corresponds to “the combinationof the user identification information and the password is stored in thestorage unit” of claim 3), the determination of Step 34 is affirmative,and the flow goes to Step 36, and the access source IP address (sourceIP address) is extracted from the HTTP data of the receivedauthentication request packet, and the user-agent information isextracted from the HTTP header of the authentication request packet.Step 36 corresponds to the extraction unit according to the invention(in particular, the extraction unit of claim 2). In the next Step 38,the user-agent information corresponding to the user ID extracted inStep 30 is extracted from the usage history table stored in HDD 12C, andthe extracted usage history information is stored in the memory 12B.

Areas for storing usage history information shown in FIG. 4 for eachuser (valid user), who applies for the usage of the online financialtransaction acceptance service and the user ID is given in advance, isprovided in the usage history table according to the embodiment. Areasfor storing and registering a customer ID, a transaction suspensionflag, a special environment flag, a verification determinationthreshold, and each piece of information of an index, and further areaswhere two sets of the access source IP address and the user-agentinformation can be registered are provided in a usage historyinformation storage area corresponding to each user.

The customer ID which is generated from an account number registered ina customer master by using a hash function is registered in the customerID area in advance. The transaction suspension flag is a flag whichindicates whether or not the authentication in a normal route (based onthe access source IP address and the user-agent information) is stopped,and 0 (zero) (meaning that the authentication is valid in the normalroute) which is an initial value of the transaction suspension flag isinitially set in the transaction suspension flag area. The specialenvironment flag is a flag which indicates whether or not an environmentfor the usage of the user is special, and 0 (zero) (meaning the normalenvironment) which is an initial value of the special environment flagis initially set in the special environment flag area. The index id isinformation which indicates which of the two sets of the access sourceIP address and the user-agent information (IP0 and UA0, and IP1 and UA1)registered as the usage history information are the latest, and Aninitial value 0 (zero) (meaning that IP0 and UA0 are the latest) is setin the index area. Blanks (no information) are set as the initial valuein the access source IP address area and the user-agent informationarea, respectively.

In the above Step 38, the customer master (not shown) is searched byusing the user ID extracted in the previous Step 30 as a key, andthereby the account number of the bank account possessed by the user towhom the user ID is imparted is extracted, and then, the customer ID isobtained from the extracted account number by using the hash function,the usage history table is searched by using the obtained customer ID asa key, and thereby the usage history information corresponding to theuser ID is extracted. In the next Step 40, it is determined whether ornot the transaction suspension flag in the extracted usage historyinformation is 1 (one). When the determination is negative, the flowgoes to Step 42, and it is determined whether or not at least one set ofthe access source IP address and the user-agent information isregistered in the extracted usage history information.

As described above, in the usage history information area, blanks areset as the initial value in the access source IP address area and theuser-agent information area. When the user who applies for the usage ofthe online financial transaction acceptance service accesses to theonline financial transaction web site more than one time, the accesssource IP address and the user-agent information extracted from theauthentication request packet in Step 36 is registered as the usagehistory information (details are described later). When the accesssource IP address and the user-agent information has been alreadyregistered as the usage history information, the determination of Step42 is affirmative, and the flow goes to Step 44, and the access sourceIP address and the user-agent information extracted from theauthentication request packet in Step 36 are verified against the accesssource IP address and the user-agent information registered as the usagehistory information.

The verification of the IP address is performed as follows. The IPaddress is a four-byte data. In the embodiment, when the access sourceIP address is registered in the access source IP address area, a hashvalue is computed for each byte by using the hash function, and the fourhash values are registered as the access source IP address. Therefore,the hash value is also computed for each byte for the access source IPaddress extracted in Step 36, the obtained four hash values are comparedto the four hash values registered in the access source IP address area,and a coincidence ratio is obtained in hash value unit. The obtainedcoincidence ratio is compared with a verification determinationthreshold set as the usage history information, and when the coincidenceratio is equal to or higher than the threshold, it is determined thatthe current access source IP address “corresponds to” the registered IPaddress, and when the coincidence ratio is lower than the threshold, itis determined that the current access source IP address “does notcorrespond to” the registered IP address.

In the mode in which the client terminal 18A is directly connected tothe Internet 16 as shown in FIG. 1, there is a case in that the IPaddress (global IP address) of the client terminal 18A may be fixed inadvance by a contract with the provider, and there is another case inthat an indefinite IP address may be allocated by the provider each timeof connection to the Internet 16 (one of the IP addresses within a fixedrange which the provider has been secured for the allocation inadvance). In the connection mode in which the client terminal 18B isconnected to the Internet 16 through the proxy server 22 placed in thefirm as shown in FIG. 1, for example, in the case where the firm obtainsthe dedicated domain to secure the IP addresses within a fixed range forthe allocation in advance, the packet transmitted from the clientterminal 18B is transmitted to the Internet 16 after the proxy server 22overwrites the source IP address set in the IP header with one of the IPaddresses within the fixed range which the firm has secured for theallocation in advance.

Accordingly, even with a client terminal 18 of which the allocated IPaddress is indefinite, because the allocated IP address falls within thefixed range (the allocated IP address has the same upper bytes), whenthe online financial transaction web site is accessed from the sameaccess source (address of the client terminal 18 on the Internet 16) asthe case where the online financial transaction web site is accessedpreviously, it can be determined that the current IP address correspondsto the registered IP address by determining whether or not the currentIP address corresponds to the registered IP address based on whether ornot the coincidence ratio of the IP address is equal to or higher thanthe threshold.

Regarding the user-agent information, when the current user-agentinformation is identical to the registered user-agent information, it isdetermined that the current user-agent information “corresponds to” theregistered user-agent information, and when the current user-agentinformation is not identical to the registered user-agent information,it is determined that the current user-agent information “does notcorrespond to” the registered user-agent information. The abovedetermination made by the verification of the access source IP addressand the user-agent information corresponds to the invention described inclaim 4. In the case where the two sets of the access source IP addressand the user-agent information are registered as the usage historyinformation, the access source IP address and the user-agent informationextracted from the authentication request packet are verified againstthe registered two sets of the access source IP address and theuser-agent information respectively.

In the next Step 46, it is determined which of “success”, “conditionalsuccess”, or “failure” corresponds to the authentication of the useroperating the client terminal 18 of the authentication request packetsource based on the verification result of the access source IP addressand the user-agent information in Step 44, and the flow is branched inaccordance with the determination result. The determination is madeaccording to a determination table shown in FIG. 5. In FIG. 5, “OK”corresponds to the case in which it is determined in the verification ofStep 44 that the current access source IP address or the currentuser-agent information correspond to the registered access source IPaddress or the registered user-agent information respectively, and “x”corresponds to the case in which it is determined that the currentaccess source IP address or the current user-agent information does notcorrespond to the registered access source IP address or the registereduser-agent information respectively. In FIG. 5, the “latest” accesssource IP address and the “latest” user-agent information express theaccess source IP address and the user-agent information which areindicated by the index id of the usage history information in the twosets of the access source IP address and the user-agent informationregistered as the usage history information, and the “previous” accesssource IP address and the “previous” user-agent information express theother access source IP address and the other user-agent information. Inthe case where only one set of the access source IP address and theuser-agent information (“latest” information) is registered as the usagehistory information, assuming that both the verification result of the“previous” access source IP address and the “previous” user-agentinformation do not correspond to the registered access source IP addressand the registered user-agent information, the determination of Step 46is made. The above Steps 44 and 46 as well as the later-mentioned Step64 correspond to the determination unit according to the invention (adetermination unit of claims 2 to 8, in particular).

In the case where the verification result of the previous Step 44satisfies a condition (for convenience, referred to as a firstcondition) that “the access source IP address and the user-agentinformation extracted from the authentication request packetrespectively correspond to at least one set of the access source IPaddress and the user-agent information in the two sets of the accesssource IP address and the user-agent information registered as the usagehistory information,” because it can be deemed that the current accesshas the same access source and the client terminal 18 as the case wherethe same user accesses the online financial transaction web sitepreviously, there is the extremely high possibility that the useroperating the client terminal 18 of the authentication request packetsource is a valid user. Therefore, in Step 46, in the above case, it isdetermined that the authentication is “success” as shown by“authentication success” in FIG. 5.

On the other hand, when the verification result of the previous Step 44satisfies a condition (for convenience, referred to as a secondcondition) that “no set of the access source IP address and theuser-agent information which corresponds to the access source IP addressand the user-agent information extracted from the authentication requestpacket exists in the sets of the access source IP address and theuser-agent information registered as the usage history information,”because at least one of the access source or the client terminal 18 inthe current access differs from the case where the same user accessesthe online financial transaction web site previously, there is highpossibility that the user operating the client terminal 18 of theauthentication request packet source is not a valid user.

However, there is possibility that the user among the many users mayhave a special usage environment, for example, the user possesses themany client terminals 18 which can be used to access the onlinefinancial transaction web site, and the user accesses the onlinefinancial transaction web site through an indefinite client terminal 18among the many client terminals 18 (in this case, there is highprobability that the pieces of user-agent information differ from oneanother in each access), or the user uses different hot spots in eachtime to access the online financial transaction web site by using aportable client terminal 18 such as a notebook PC (in this case, thereis high probability that the access source IP addresses differ largelyfrom one another in each access), and such users who have the specialusage environment also correspond to the second condition.

Therefore, in the case where the verification result in Step 44satisfies a condition (for convenience, referred to as a thirdcondition) that “it is determined that both the two sets of the accesssource IP address and the user-agent information registered as the usagehistory information correspond to the access source IP address extractedfrom the authentication request packet or the user-agent informationextracted from the authentication request packet,” it is determined inStep 46 that the authentication is “conditional success” as shown by“authentication conditional success” in FIG. 5. In the case where theverification result in Step 44 satisfies the second condition while notsatisfying the third condition, it is determined that the authenticationis “failure” as shown by “authentication failure” in FIG. 5.

When it is determined that the authentication is “success” in Step 46,the flow goes to Step 48 to determine whether or not the specialenvironment flag of the usage history information is 1 (one). When thedetermination is negative, the flow goes to Step 52, the predeterminedprocessing module of the start-up source is notified of theauthentication success. In this case, the predetermined module performsthe process of distributing the predetermined web page, which isdistributed only to the user who is confirmed to be a valid user, to theclient terminal 18 of the authentication request packet source isperformed. In the next Step 54, it is determined whether or not theaccess source IP address and the user-agent information extracted fromthe authentication request packet correspond to the “latest” accesssource IP address and the “latest” user-agent information indicated bythe index id in the access source IP address and the user-agentinformation registered as the usage history information.

When the determination is affirmative, the flow goes to Step 60, the“latest” access source IP address and the “latest” user-agentinformation registered as the usage history information are overwrittenwith the access source IP address and the user-agent informationextracted from the authentication request packet, and the access sourceIP address and the user-agent information extracted from theauthentication request packet are registered, and then, the flow goes toStep S62. When the determination of Step 54 is negative, the flow goesto Step 56, the “previous” access source IP address and the “previous”user-agent information (the access source IP address and the “previous”user-agent information which are not indicated by the index id)registered as the usage history information are overwritten with theaccess source IP address and the user-agent information extracted fromthe authentication request packet, and the access source IP address andthe user-agent information extracted from the authentication requestpacket are registered (in the case where the access source IP addressand the user-agent information to be overwritten are the “blanks”, theupdate registration of Step 56 corresponds to the “additional storage”of claim 5). In the next Step 58, the access source IP address and theuser-agent information which has been overwritten and registered in Step56 are changed to the “latest” access source IP address and the “latest”user-agent information by inverting the bit of the index id.

In Step 62, the usage history information stored in the memory 12B isre-written in the usage history table, and thereby the usage historyinformation of the usage history table is updated and the userauthentication process ends. Like the above Steps 60 and 56, the accesssource IP address and the user-agent information registered as the usagehistory information are overwritten with the access source IP addressand the user-agent information extracted from the authentication requestpacket, and the access source IP address and the user-agent informationextracted from the authentication request packet are registered.Therefore, the accuracy of verification of Step 44 and the accuracy ofdetermination of Step 46 can be improved when the user authenticationprocess is performed again for the same user. Steps 54 to 62 correspondto the information management unit according to the invention (theinformation management unit of claims 2, 5, and 11, in particular).

On the other hand, when it is determined that the authentication of theprevious Step 46 is “failure”, the flow goes to Step 68, and thetransaction suspension flag in the usage history information is set to 1(one). Even in the case where it is determined that the authenticationin Step 46 is “failure”, there is the possibility that the useroperating the client terminal 18 of the authentication request packetsource may be a valid user. With this point in view, in the next Step70, an electronic mail address which is stored in the authenticationinformation DB so as to correspond to the user ID extracted in Step 32is read, and a re-authentication request e-mail is transmitted to theread electronic mail address. In an example shown in FIG. 6, a link 100to the web page dedicated to the re-authentication is added to there-authentication request e-mail which confirms whether or not the useroperating the client terminal 18 of the authentication request packetsource is a valid user by an authentication method different from thenormal route. Step 70 corresponds to the transmission unit of claim 9.

In Step 72, the predetermined processing module of the start-up sourceis notified of the authentication failure, and the flow goes to Step 54.Accordingly, as described above, the update and registration of theaccess source IP address and the user-agent information extracted fromthe authentication request packet are performed in the usage historyinformation, and the usage history information is re-written in theusage history table. Then, the user authentication process is ended.

As described above, the transaction suspension flag is set to 1 (one)when it is determined that the authentication of Step 46 is “failure”,and therefore, in the case where the user authentication process isperformed again to the same user, the determination of Step 40 isaffirmative and the flow goes to Step 70, and thereby the authenticationis not performed in the normal route (the authentication based on theaccess source IP address and the user-agent information), but there-authentication request e-mail is transmitted again (Step 68) tonotify the predetermined processing module of the start-up source of theauthentication failure again (Step 72). Accordingly, in the case wherethe previous user authentication process in which it is determined inStep 46 that the authentication is “failure” is performed by an illegalaccess of a third party which illegally obtains the user ID and thepassword, the existence of the illegal access can be detected insteadalthough the authentication is “failure” when a valid user accesses theonline financial transaction web site to receive the authentication.

In the case where it is determined in Step 46 that the authentication is“failure” even if the user operating the client terminal 18 of theauthentication request packet source is a valid user, the user receivesthe re-authentication request e-mail transmitted in the previous Step70, the user accesses the web page dedicated to the re-authenticationfrom the link 100 added to the received re-authentication requeste-mail, and the user receives a predetermined re-authenticationprocedure through the web page dedicated to the re-authenticationdisplayed on the display of the client terminal 18. In the case wherethe user is confirmed to be a valid user by the re-authenticationprocedure, the processing module which performs the user authenticationprocess is notified of the re-authentication success. In order to accessthe web page dedicated to the re-authentication, it is necessary to havethe environment in which the re-authentication request e-mail can bereceived, and it can be deemed there is extremely high possibility thata person who accesses the web page dedicated to the re-authentication toreceive the re-authentication procedure is a valid user at that time,and accordingly the burden to the user can be reduced by a relativelysimple re-authentication procedure.

On the other hand, when the processing module which performs the userauthentication process is notified of the re-authentication success, theprocessing module performs a usage history table update process shown inFIG. 7. That is, the user ID of the user who is confirmed to be a validuser by the re-authentication procedure is added as information to theabove re-authentication notification, and first, in Step 80, the user IDof the user who is confirmed to be a valid user is extracted andobtained. In the next Step 82, the usage history informationcorresponding to the user ID obtained in Step 80 is extracted from theusage history table, and the extracted usage history information isstored in the memory 12B. In Step 84, in the extracted usage historyinformation, the transaction suspension flag is returned to 0 (zero),and the special environment flag is set to 1 (one). In Step 86, theusage history information is re-written in the usage history table, andthe usage history table update process is ended. By returning thetransaction suspension flag to 0 (zero) as described above, in the casewhere the user authentication process is performed to the same useragain, the determination of Step 40 is negative to resume theauthentication in the normal route. Step 84 corresponds to theinformation management unit of claim 8.

When it is determined that the authentication of Step 46 is “conditionalsuccess”, the flow goes to Step 64, and it is determined whether or notthe special environment flag in the usage history information is set toone. When the authentication is “conditional success”, as describedabove, there is the high probability that the user operating the clientterminal 18 of the authentication request packet source has the specialusage environment, however, it is also undeniable that the illegalaccess is performed by the third party. Therefore, in the “conditionalsuccess” in the embodiment, the authentication success in there-authentication procedure is a condition of the authenticationsuccess. When the determination of Step 64 is negative, namely, when theprocessing module is not notified of the re-authentication success, theflow goes to Step 68 to perform the process of transmitting there-authentication request e-mail as described above.

When the determination of Step 64 is affirmative, namely, when theprocessing module is notified of the re-authentication success toperform the usage history table update process (FIG. 7), the flow goesto Step 66, and the electronic mail address which is stored in theauthentication information DB so as to correspond to the user IDextracted in Step 32 is read, and a confirmation e-mail of which exampleis shown in FIG. 8 is transmitted to the read electronic mail address. Adata and time and the like are described in the confirmation e-mail, andin the event that the current access is the illegal access, a valid userreceives and refers to the confirmation e-mail, which allows theexistence of the illegal access to be detected. After the process ofStep 66 is performed, the flow goes to Step 52 to notify thepredetermined processing module of the start-up source of theauthentication success, and then, in the processes from Step 54, theaccess source IP address and the user-agent information extracted fromthe authentication request packet are overwritten and registered in theusage history information, and the usage history information isre-written in the usage history table, and then, the user authenticationprocess is ended. Accordingly, it can be determined whether or not theuser is a valid user even for the user having the special usageenvironment.

When the special environment flag is set to 1 (one), when thedetermination of Step 46 satisfies the third condition as describedabove, it is determined that the authentication is “success”, andtherefore there is a drawback of reducing the degree of securityslightly. Therefore, in the case where the first condition is satisfiedin the determination of Step 46 to determine that the authentication is“success”, it is determined in Step 48 whether or not the specialenvironment flag is set to 1 (one), and when the determination isaffirmative, the special environment flag is returned to 0 (zero) inStep 50, and then the flow goes to Step 52. Accordingly, the drawbackcan be dissolved.

Finally, the case in which the user who applies for the usage of theonline financial transaction acceptance service first accesses theonline financial transaction web site at first time will be described.In this case, the access source IP address and the user-agentinformation are not registered in the usage history information, and theauthentication is hardly performed in the normal route. Therefore, thedetermination of Step 42 is negative, and the flow goes to Step 68, andthe transaction suspension flag is set to 1 (one) as described above,and the process of transmitting the re-authentication request e-mail isperformed to receive the predetermined re-authentication procedurethrough the web page dedicated to the re-authentication. In this case,in Step 60, the access source IP address and the user-agent informationare also registered in the usage history information, and thetransaction suspension flag is returned to 0 (zero) when there-authentication is successful. Therefore, the authentication in thenormal route is performed in the subsequent accesses.

The maximum two sets of the access source IP address and the user-agentinformation are registered for each user are registered as above,however, it is not limited to this, more than two sets of the accesssource IP address and the user-agent information may be registered foreach user. In such cases, unless a set of the access source IP addressand the user-agent information which is determined to correspond to anew access source IP address and a new user-agent information extractedfrom the authentication request packet exists in the already registeredsets of the access source IP address and the user-agent information, thenew set of the access source IP address and the user-agent informationis additionally registered until the number of registered sets of theaccess source IP address and the user-agent information reaches theupper limit value, and the earliest set of the access source IP addressand the user-agent information may be overwritten with the new set ofthe access source IP address and the user-agent information and the newset of the access source IP address and the user-agent information isregistered after the number of registered sets of the access source IPaddress and the user-agent information reaches the upper limit value.The above item corresponds to the invention of claim 10.

Alternatively, it is not necessary that the upper limit value isprovided for the number of registered sets of the access source IPaddress and the user-agent information. For example, in consideration ofthe special usage environment in which the access is made by selectivelyusing the many client terminals 18 or many kinds of the access sources(for example, many hot spots), the sets of the access source IP addressand the user-agent information are registered without the upper limit(When the set of the access source IP address and the user-agentinformation, which is determined to correspond to the new access sourceIP address and the new user-agent information extracted from theauthentication request packet exists in the already registered sets ofthe access source IP address and the user-agent information, the set ofthe access source IP address and the user-agent information isoverwritten with the new set of the access source IP address and theuser-agent information and the new set of the access source IP addressand the user-agent information is registered, otherwise, the new accesssource IP address and the new user-agent information are additionallyregistered), and the set of the access source IP address and theuser-agent information which exceeds a threshold of an elapsed timesince the registration, or which exceeds a threshold of times when it isdetermined that the set of the access source IP address and theuser-agent information does not corresponds to the new access source IPaddress and the new user-agent information may be deleted. In thisaspect, although there is a drawback of possibly enlarging the usagehistory information, it can be determined in Step 46 that theauthentication is “success” even in the user having the special usageenvironment, and accordingly, it is not necessary to provide“conditional success” of the authentication, and the security canfurther be improved.

The client terminal 18 formed by the PC or the like is described as theterminal device according to the invention by way of example, however,it is not limited to this, the client terminal 18 may be a portableterminal such as PDA and a portable telephone which has a function ofaccessing the Internet. This kind of portable terminal is connected tothe Internet through a gateway server provided in a wirelesscommunication network, in particular, the gateway server temporarilyreceives information which is transmitted from the portable terminal toaccess a given web site, and the information is converted into thepacket pursuant to the protocol (IP: protocol of the Internet layer,TCP: protocol of the transport layer, and HTTP: protocol of theapplication layer) applied to the communication through the Internet 16,and one of the IP addresses within a fixed range which a wirelesscarrier has secured in advance is set as the source IP address to the IPheader, and information including a name of the wireless carrier, a typeand a model number of the portable terminal, and a version of a browserare set as the user-agent information to the HTTP header, and then, theuser-agent information is transmitted to the Internet 16. Depending on acontract mode with the wireless carrier, the gateway server and aspecific web server are connected with a dedicated line, and there is acase in that the packet to the specific web server may be transmittedfrom the gateway server not through the Internet 16. Even in suchcommunication modes, the source IP address and the user-agentinformation are set in the packet similarly as above. The range of theIP address secured for the allocation depends on each wireless carrier.Accordingly, even if the terminal device is the portable terminal, itcan be confirmed whether or not the user operating the portable terminalis a valid user by applying the invention.

Further, in the embodiment, the invention is applied to the userauthentication in the online financial transaction web site whichprovides the online financial transaction acceptance service, however,it is not limited to this, the invention may be applied to a userauthentication or a user validation in any site. In the aboveembodiment, the user authentication to which the invention applied isused in conjunction with the user authentication in which the user IDand the password are used, however, since the high-accuracy uservalidation (authentication) is not required as long as the web siteprovides information-transmitting service in which certain informationis distributed at each time the user who registers in advance requests asimple user identification information such as an electronic mailaddress. Therefore, the user authentication based on the password may beomitted, and only the user validation (authentication) to which theinvention is applied may be performed based on the user identificationinformation such as the electronic mail address inputted by the user.

Although the user validation (authentication) is performed by using theaccess source IP address and the user-agent information in the aboveembodiment, however, it is not limited to this, for example, in the casewhere only the access from a fixed terminal device is permitted for eachuser like a web site where only an access from a client terminal inwhich an electronic certificate is installed is permitted for each user,only the user-agent information may be stored so as to correspond to theuser identification information, and the user validation(authentication) may be performed based on whether or not the user-agentinformation is verified against the registered user-agent information.

EXPLANATION OF REFERENCE NUMERALS

-   10 computer system-   12 web server-   12C HDD-   16 Internet-   18 client terminal

1. A user validation apparatus comprising: a memory, and a processorprogrammed to: extract user-agent information and an access sourceinternet protocol (IP) address in an HTTP header of a packet receivedfrom a terminal device operated by an individual user by applying HTTPas a protocol of an application layer; store the extracted user-agentinformation and the extracted access source IP address in the memory asusage history information that corresponds to user identificationinformation of the individual user; determine that the user isconditionally valid, when: the received user login information isidentical to login information stored in the memory, and (a) theextracted user-agent information corresponds to user-agent informationstored in the memory, but the extracted IP address does not correspondto IP address stored in the memory, or (b) the extracted user-agentinformation does not correspond to user-agent information stored in thememory, but the extracted IP address corresponds to IP address stored inthe memory; and transmit a further authentication information based oncontact information corresponding to the received user login informationand stored in the memory, when the user is determined to beconditionally valid.
 2. A user validation apparatus comprising: amemory, and a processor programmed to: extract user-agent informationfrom HTTP header of a packet received from the terminal device; storethe extracted user-gent information or the extracted access source IPaddress onto the memory as usage history information that corresponds touser identification information of the individual user; determine thatthe user is conditionally valid, when: (i) the received user logininformation is identical to login information stored in the memory, and(ii) the extracted user-agent information does not correspond touser-agent information stored in the memory; and transmit a furtherauthentication information based on contact information corresponding tothe received user login information and stored in the memory, when theuser is determined to be conditionally valid.
 3. The user validationapparatus according to claim 2, wherein the processor is furtherprogrammed to: request re-authentication to the given terminal devicefrom which the user login information is transmitted, when the useroperating the given terminal device is determined to be theconditionally valid user.
 4. The user validation apparatus according toclaim 2, wherein the processor is further programmed to: store aplurality of sets of the access source IP addresses and the user-agentinformation.
 5. The user validation apparatus according to claim 2,wherein the processor is further programmed to: additionally store a newaccess source IP address or new user-agent information.
 6. A uservalidation method executed by a computer comprising: receiving userlogin information from a terminal device operated by a user; extractinguser-agent information from HTTP header of a packet received from theterminal device; determining that the user is conditionally valid, when:(i) the received user login information is identical to logininformation stored in a first database, and (ii) the extracteduser-agent information does not correspond to user-agent informationstored in a second database; and transmitting a further authenticationinformation based on contact information corresponding to the receiveduser login information and stored in a third database, when the user isdetermined to be conditionally valid.
 7. The user validation methodaccording to claim 6, wherein the contact information is an electronicmail address.
 8. The user validation method according to claim 6,wherein the further authentication information is a confirmation link.9. The user validation method according to claim 6, further comprising:updating the second database, when the further authentication isperformed successfully.